Home' Defence Technology Review : DTR FEB 2015 Contents 31
DEFENCE TECHNOLOGY REVIEW | ISSUE 06 | FEB 2015
There will be impassioned arguments around this difference, but
there is no doubt that the importance of raw ‘g’ in air combat ef-
fectiveness has dropped markedly over recent decades in favour of
improved SA. The LO capable F-35B, possessing exceptional SA and
armed with the AIM-120C Advanced Medium Range Air-to-Air
Missile and new generation short-range air-to-air missiles, plus a
sustained turn rate much better than legacy STOVL aircraft, will be
a highly capable air combat adversary.
Finally, weapons bay capacity. Again, the original KPPs reflected
the reality of STOVL challenges and called for the F-35B to carry a
1000lb Joint Direct Attack Munition (JDAM) internally, as opposed
to the 2000lb JDAM requirement for F-35A and C variants.
Early F-35B designs attempted to achieve a ‘common’ 2000lb
capable weapons bay, but reality caught up with Lockheed Martin
around 2004, and the F-35B reverted to a smaller ‘KPP compliant’
bay. However, the F-35B can still carry 2000lb JDAMs externally if
required, and in any case, the need for these very large weapons is
infrequent: recent operations show that 500lb class air-to-ground
munitions are the most frequently used by a large margin. Again,
this drop in heavy ordnance capability would not likely be a deal
breaker for the (ADF).
In any event, the F-35B offers a tremendous step forward in
STOVL capability compared with that offered by the Harrier family
of aircraft, which have, for over 30 years, delivered highly effective
combat capability all over the globe.
So, it’s true that, in some respects, the F-35B has more limited ca-
pability than the F-35A. But these do not appear to be ‘decisive’ or
‘critical’ shortfalls. But – and the value of this ‘but’ cannot be overes-
timated – in many scenarios, it delivers the important capability to
operate from a ship much closer to the required area of operations.
Our defence leaders have to decide whether that is a capability trade
off worth making.
So let’s look at the other main area of contention – the practicality
of putting the F-35B on the ‘Canberra’ class LHDs.
Integrating Aircraft and Ships
It’s best to start by understanding that putting military aircraft on
ships has never been easy. Warships, even the massive US Navy
(USN) nuclear-powered aircraft carriers, are not and never will be
just ‘floating airfields’ – the raw constraints of physical space have
driven naval aviators to develop new ways of launching, recovering,
arming, maintaining and repairing aircraft since the earliest days.
But they have consistently succeeded. Effective, safe and sustain-
able embarked air power has been demonstrated from a wide vari-
ety of ship/aircraft combinations over the past 100 years. Maritime
fixed-wing aviation is an achievable art – and STOVL makes it even
Successful maritime aviation depends on a little known discipline
called ‘ship/aircraft integration’. This is a systems engineering chal-
lenge, requiring thorough understanding and control of the various
interfaces between the ship and the aircraft. So, how closely are the
F-35B and the LHD interfaces currently aligned? Remember, it’s
been regularly asserted that the LHD is ‘not designed to operate the
F-35B’ or that the F-35B ‘will not be compatible’ with the LHD.
To assess the practicability question, we need to understand the
various types of ship/aircraft interface. They can be grouped as fol-
The operating interface – launching and recovering, including
movement around the flight deck, with ship motion;
The environmental interface – includes aircraft weight, size, jet
blast and noise;
The information interface – becoming a major aspect, includes
the required mission support systems, communication and iden-
tification, and not least the means of exploiting the intelligence,
surveillance and reconnaissance outputs from the F-35B. Also in-
cludes the required guidance systems for launch and recovery;
The support interface – how the ship provides the required
support capabilities to the aircraft, including fuel, weapons and
maintenance. A key driver for manpower requirements as well as
hangar and flight deck layouts.
The important issue of personnel requirements for F-35B opera-
tions will also be examined.
Let’s take each of these issues in turn, and see how much is known
from publicly available information.
The Operating Interface
At the outset, it’s vital to appreciate two very salient facts.
The first is that the F-35B has been specifically designed to op-
erate from ships like the LHD. It has had to meet requirements
for operating from USN Wasp-class amphibious assault ships, as
well as some UK specifications for ski jump launches. Wasp-class
flight decks and spaces are not dissimilar to those on the LHDs,
although they do not have the benefit of a ski-jump.
The second is that the LHD class on which the Canberra-class has
been based has also been designed with F-35B in mind. The orig-
inal Spanish Juan Carlos I design was required from the outset to
embark the F-35B, and detailed technical information was made
available from the US to Spain to assist in this process. All these
requirements were retained in the two Canberra-class LHDs.
So, looking at F-35B launch and recovery, the LHD flight deck
would allow short take-off (STO) launches at required mission
weights without the ski-jump. With the ski jump – already facto-
ry-fitted – safer and more effective (higher weight) launches will be
possible. We are looking at something in the order of 1,500kg of extra
payload with no penalty except a safer take-off. Remember that the
aircraft is specifically required to be able to launch from ski-jumps.
For landings, the F-35B’s flight control system has been carefully
designed to allow safe and accurate recovery to small deck areas with
low pilot workload in all conditions. The nose wheel steering and en-
gine controls also support aircraft movement on small or congested
Summary: the operating interface presents low risk. The ski-jump
on the Canberra-class offers significant operational advantages over
USN amphibious assault ship designs and would mitigate the F-35B’s
differential in performance compared with the F-35A.
The Environmental Interface
The F-35B design was sized by the requirement to use the Wasp-
class flight deck, elevators and hangars. These are small spaces. It
drove the wingspan and length of the aircraft, landing gear geome-
try and other aspects. As we already know, the RAN’s LHD source
design accepts the F-35B’s weight and size. The elevators, for in-
stance, are sized to 27 tonnes – very near the aircraft’s maximum
possible weight. So the aircraft will fit on board and can be moved
But it is F-35B jet blast that has become a contentious issue, so let’s
address that. Since the advent of maritime jet aircraft, handling jet
blast in the confined space of a ship has been a major issue. USN car-
riers carry large and complex jet blast deflectors for launching, and
deck heating on launch was a major issue for UK carriers throughout
the 1960s and 1970s with the F-4 Phantom. The first generation of
AVIATION IS AN ACHIEVABLE
ART – AND STOVL MAKES IT
EVEN MORE ACHIEVABLE
WITH THE SKI JUMP – ALREADY FACTORY-FITTED – SAFER AND
MORE EFFECTIVE (HIGHER WEIGHT) LAUNCHES WILL BE POSSIBLE.
WE ARE LOOKING AT SOMETHING IN THE ORDER OF 1,500KG OF
EXTRA PAYLOAD WITH NO PENALTY EXCEPT A SAFER TAKE-OFF
ABOVE: An F-35B taking off from the amphibious assault
ship USS Wasp in August 2013. The ski-jump inherent in the
Canberra-class LHD design allows for higher maximum take-off
weights and therefore higher payload capacity for weapons and
fuel. It is a design advantage not enjoyed by flat-tops such as the
Wasp-class. Images: USN
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